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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

16150 results found.

  1. GRB 230510A: LCOGT Optical Upper Limit
  2. GRB 230510A: Gaoyazi/GOT optical upper limit
  3. GRB 230510A: Nanshan/NEXT optical afterglow detection
  4. GRB 230506B: Swift/UVOT further analysis
  5. GRB 230506C: SAO RAS optical observations
  6. GRB 230307A: JWST second-epoch observations
  7. GRB 230506C: spectro-imaging observations of the optical afterglow with T193-OHP
  8. GRB 230506B: LCOGT Optical Upper Limits
  9. GRB 230506C: Swift/UVOT Upper Limits
  10. GRB 230506C: NUTTelA-TAO / BSTI Early Optical Limits
  11. GRB 230506B: MASTER optical observations
  12. GRB 230420A: Mondy optical afterglow detection, TSHAO, CrAO optical upper limit
  13. GRB 230420A: AROMA-N Optical Upper Limit
  14. GRB 230427A: NOT optical upper limit
  15. GRB 230427A: TSHAO, SAO RAS, AbAO optical upper limit
  16. GRB 230427A: Gaoyazi/GOT optical upper limit
  17. GRB 230427A: Nanshan/HMT optical upper limit
  18. GRB 230427A: Osservatorio Astronomico Nastro verde upper limit
  19. GRB 230427A: GIT optical upper limit
  20. GRB 230427A: Bassano Bresciano Observatory upper limit
  21. GRB 230427A: GMG upper limit
  22. GRB 230427A : OHP/T193 optical upper limit
  23. GRB 230427A: BOOTES-5/JGT afterglow detection
  24. GRB 230426A: MASTER OT J023135.16-792104.8 optical counterpart discovery
  25. GRB 230427A: MITSuME Akeno optical upper limits
  26. GRB 230427A: Swift detection of a burst with an optical counterpart
  27. GRB 230423A: Swift/UVOT Upper Limits
  28. GRB 230420A: Lowell Discovery Telescope Optical Detection
  29. GRB 230420A: Swift/UVOT Upper Limits
  30. GRB230420A: VLT optical observation
  31. GRB 230420A: MITSuME Akeno optical observation
  32. GRB 230420A: NOT optical afterglow confirmation
  33. GRB 230420A: Gaoyazi/GOT optical upper limit
  34. GRB 230420A: BOOTES-5/JGT optical afterglow detection
  35. GRB 230420A: LCOGT Optical Upper Limit
  36. GRB230414B: VIRT Optical Upper Limit
  37. GRB 230414B: Nickel and KAIT telescope optical observations
  38. GRB 230414B: Swift/UVOT Detection
  39. GRB 230414B: Osservatorio Astronomico Nastro Verde - Sorrento: optical observations
  40. VIRT optical transient detection
  41. GRB 230414B: 3.6m DOT Optical observations, slow decay at early epochs
  42. GRB 230307A: iTelescope optical upper limit (likely)
  43. GRB 230414B: Montarrenti Observatory late time optical afterglow detection
  44. GRB 230414B: Lulin 40cm-SLT optical limit
  45. GRB 230414B: Bassano Bresciano Observatory optical observations
  46. GRB 230414B: AbAO optical observations
  47. GRB 230409B: 3.6m DOT near-infrared detection, afterglow confirmation
  48. GRB 230414B: Dabancheng/GHOST optical observations
  49. GRB 230414B: slow optical light curve decay
  50. GRB 230414B: SAO RAS optical observations
  51. GRB 230414B: 1.3m DFOT Optical observations
  52. GRB 230414B (correction GRB name in the GCN 33615): Mondy optical afterglow candidate
  53. GRB 230414B: Nanshan/HMT optical afterglow detection
  54. GRB 230414A: Mondy optical afterglow candidate
  55. IceCube-230405A: BOOTES-4/MET Optical Upper Limits
  56. GRB 230409B: Mondy optical upper limit
  57. GRB 230409B: OHP/T193 optical upper limit
  58. GRB 230405B: MeerLICHT upper limits
  59. GRB 230405B: Swift/UVOT Upper Limits
  60. GRB 230307A: JWST observations consistent with the presence of a kilonova
  61. GRB 230328B: Multa observatory optical afterglow observation
  62. GRB 230328B: Swift/UVOT Detection
  63. GRB 230328B : GRANDMA/Kilonova-Catcher optical detection
  64. GRB 230328B: 3.6m DOT multiband optical observation
  65. GRB 230328B: Nanshan/NEXT 2nd optical observation
  66. GRB 230328B: Liverpool Telescope afterglow detection
  67. GRB 230328B: OHP/T120 optical observations
  68. GRB 230328B: GIT optical follow-up
  69. GRB 230328B: OASDG optical observations
  70. GRB 230328B: Nanshan/NEXT optical upper limit
  71. GRB 230328B: Mondy, AbAO and Kitab optical observations
  72. GRB 230328B: Mondy optical afterglow confirmation
  73. GRB 230328B: Swift detection of a burst with an optical afterglow
  74. GRB 230325A: Swift/UVOT Upper Limits
  75. GRB 230325A: X-shooter optical afterglow and redshift
  76. GRB 230322B: Swift detection of a burst with optical counterpart
  77. GRB 230314A: TURBO Optical Upper Limit
  78. GRB 230307A: Continued Gemini-South observations confirm rapid optical fading
  79. GRB 230307A: ATCA radio detection
  80. GRB 230307A: INTEGRAL upper limit on Hard X-ray afterglow
  81. GRB 230307A: Swift/UVOT detection
  82. Further improved IPN localization for GRB 230307A
  83. GRB 230307A: SOAR/Goodman detection of the possible host galaxy
  84. TESS Detection of the Optical Afterglow of GRB230307A
  85. GRB 230307A: GECKO optical observations and detections of the afterglow
  86. GRB 230307A: Gemini-South Confirmation of the Optical Afterglow
  87. GRB 230307A: ATLAS information on the ULTRACAM optical afterglow candidate
  88. GRB 230307A: Erratum of the GCN 33441
  89. GRB 230204B: MASTER detection of an object near NTT Optical Afterglow Candidate
  90. GRB 230307A: Possible optical afterglow
  91. GRB 230228A: NUTTelA-TAO / BSTI Optical Limits
  92. GRB 230307A: optical upper limit
  93. GRB 230217A: ATCA rapid-response radio detection
  94. GRB 230228A: VIRT Optical Upper Limit
  95. GRB 230228A: Swift/UVOT Upper Limits
  96. GRB 230228A: OSN optical upper limit
  97. GRB 230228A: Mondy optical upper limit
  98. GRB 230228A: Nanshan/NEXT optical upper limit
  99. GRB 230228A: Miryang Arirang Astronomical Observatory (MAAO) 0.7-m telescope optical upper limit
  100. GRB 230217A: VLT/FORS2 optical observations and candidate counterpart

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